Breakout Session 1: Elemental Biogeochemical Cycles in Terrestrial EnvironmentsSession Chairs: Harry Beller (LBNL), Liyuan Liang (ORNL), and John Zachara (PNNL)Panelists: Derek Lovley (University of Massachusetts), Francois Morel (Princeton University), Tim Scheibe (PNNL), Jeremy Smith (University of Tennessee), Anne Summers (University of Georgia), and Philippe van Cappellen (University of Waterloo)Objective: The EMSP/NABIR/SBR programs have defined the state of fundamental science in contaminant biogeochemistry and metal/radionuclide fate and transport over the past 10 years. Seminal impacts to this scientific area have been made by many publications, the development of multidisciplinary approaches, and the performance of sophisticated field studies of unique character. While previous research has focused on the subsurface environment, elemental cycling facilitated by biosphere-metal interactions occurs more broadly in terrestrial environments including soil, groundwater, and freshwater sediments. Biosphere-metal interactions critically affect all ecosystems and respond in a dynamic manner to climatic and other environmental changes on all scales. Scientific understanding of these diverse, complex, and far-reaching processes, together with their rates, interactions, and impacts, is uneven. The intent of this session is to identify impactful scientific grand challenges (GCs) in elemental biogeochemical cycling (e.g., S, Fe/Mn, Si, trace elements, etc.) in terrestrial environments to guide future research.Content: A panel and audience discussion will identify fundamental scientific grand challenges (GC) in elemental biogeochemistry and multidisciplinary approaches to resolve them. Environments to be considered include soils, the vadose zone, groundwater, the groundwater-river mixing zone, and the hyphoreic zone. The focus will be on elemental cycling challenges that involve coupled microbiologic, hydrologic, and geochemical processes and that require a combination of molecular, mechanistic, and systems-scale approaches for comprehensive resolution and environmental prediction. The session will also consider responses of elemental biogeochemical cycling to climatic and other dynamic environmental changes. Discussions will identify two to three impactful grand challenges, example environments where they could be evaluated, balances between fine-scale and systems-scale research, and new modeling approaches that might be required.Report Out: Breakout Session 1

2:00-5:30 pm

Breakout Session 2: Toward an Integrated, Process-Level View of Biogeochemical Cycling and Carbon Flow within Terrestrial Systems Session Chairs: Baohua Gu (ORNL), Susan Hubbard (LBNL), and Alan Konopka (PNNL)Panelists: Jon Chorover (University of Arizona), Evan DeLucia (University of Illinois), Mary Firestone (UC Berkeley), TC Onstott (Princeton University), and Bill Riley (LBNL)Objective: Managed and natural terrestrial ecosystems are critically important for sustaining life. The interactions between the solid, aqueous, and biological components of ecosystem soils and underlying sediments regulate the geochemical fluxes of most life-critical elements, control the production of food and biofuel feedstock, and regulate greenhouse gases. Despite decades of research on carbon cycling in terrestrial ecosystems and the clear importance of these systems for bioenergy and climate change, a predictive understanding of the physical, chemical, and biological interactions that occur across scales and through various linked compartments of the system (atmosphere-plant-soil-vadose zone-groundwater-surface water) remains elusive. The lack of understanding hinders our ability to predict and optimize ecosystem behavior, both under current and future environmental conditions.
BER has the potential to advance such a predictive understanding through the linkage of the SBR, Terrestrial Ecosystem Science (TES), Climate Science, and BSSD programs. Recognition of the hierarchical nature and complex interactions between system components, innovative multi-disciplinary approaches, sophisticated new instrumental platforms and “omics” technologies, and multi-scale mechanistic models developed through SBR research on contaminant biogeochemistry have great potential to advance a process-level understanding of biogeochemical cycles and carbon fluxes within terrestrial ecosystems. Such understanding is required for improved predictions and ultimately for sustainable management of natural and managed ecosystems. This breakout session will explore grand challenges that leverage SBR multi-process expertise to questions of how biogeochemical cycles coupled to hydrological fluxes impact carbon dynamics in multi-compartment terrestrial systems. Content: The breakout session will identify research grand challenges (GCs) related to developing a predictive understanding of the biogeochemical basis (broadly defined) of carbon cycling; carbon storage, transformation, and sequestration; and C exchange and redistribution in complex, multi-compartment terrestrial systems. The GCs will involve coupled processes; explicitly consider the range of space and time scales relevant to energy and environmental sustainability; have field relevance and linkage; be complementary to research directions in TES; and benefit from the research perspectives and approaches developed collectively by the SBR community including environmental “omics,” molecular spectroscopy and analysis, multi-process modeling, and field characterization, monitoring, and experimentation. Deliberations will refine candidate GCs to a few examples and identify associated (i) science questions to guide scale-specific studies, (ii) molecular- to field-scale experimental and monitoring approaches that might be applied, (iii) ecosystem field site characteristics desirable for performing impactful science, and (iv) opportunities for the development of robust, process-level biogeochemical models of carbon cycling in multi-scale terrestrial systems. The session will conclude with an important discussion on how process-level models of biogeochemical cycles could contribute to improved management of ecosystem-level carbon fluxes and transformation rates. Report Out: Breakout Session 2

2:00-5:30 pm

Breakout Session 3: Subsurface Biogeochemical Processes Associated with Energy Production, Usage, and StorageSession Chairs: Scott Brooks (ORNL), Jim Fredrickson (PNNL), and Carl Steefel (LBNL)Panelists: Rick Colwell (Oregon State University), Li Li (Penn State University), George Redden (INL), and Ken Williams (LBNL)Objective: Many energy-related activities perturb the biogeochemistry of the subsurface or are themselves influenced by biogeochemical processes. A prime example is the design of geological nuclear waste repositories, where the impact of biogeochemical processes on far-field radionuclide transport will be substantial. Microbially-enhanced hydrocarbon recovery (MEHR) is another example in which perturbation of the subsurface microbiological and biogeochemical environment is used for energy extraction purposes. More knowledge is also needed of how greenhouse gas fluxes are modified by biogeochemical processes in the subsurface; the release of methane from methane hydrates due to global warming is now treated as a purely physical/hydrological process but is likely to be far more complex. Another example involves the leakage of geologically stored CO2 into drinking water aquifers, where acidification may significantly alter the biogeochemical status and where toxic metals may be potentially mobilized. The objective of this breakout session is to address the question of how energy production, usage, and storage of byproducts can impact the biogeochemistry of the subsurface, as well as to consider how the ambient or perturbed biogeochemical environment can impact the energy production and storage schemes.Content: The breakout session will identify fundamental biogeochemical grand challenges associated with the production, usage, and storage of energy in the subsurface. While these topics have been addressed by applied DOE programs for improving process efficiencies, a firm scientific underpinning for understanding the full system behavior is lacking. An overall goal is to identify cross-cutting fundamental science issues or knowledge gaps associated with multi-scale, biogeochemical reactive transport whose resolution could advance safe extraction, isolation, or storage technologies. The breakout will consider the far-field impacts of biogeochemistry on the effective design of geological nuclear waste repositories, the effects of enhanced gas recovery and carbon sequestration on subsurface microbiologic communities and their biogeochemical function, and perturbations to the subsurface as a result of inadvertent hydrocarbon releases. The effect of biogeochemistry on carbon fluxes in the deep subsurface (as distinct from the soil environment) as related to climate change will also be addressed. A desired outcome is the identification of fundamental biogeochemical research topics applicable to multiple emerging DOE mission areas. Report Out: Breakout Session 3 Slides

Highlights

Please wait

Citation and Credit

Unless otherwise noted, publications and webpages on this site were created for the U.S. Department of Energy Subsurface Biogeochemical Research program and are in the public domain. Permission to use these documents is not needed, but please credit the U.S. Department of Energy Subsurface Biogeochemical Research program and provide the URL http://doesbr.org when using them. Materials provided by third parties are identified as such and are not available for free use.